Methods of recording

Having decided what instruments you wish to install and the data that they will provide, a decision on methods of recording will need to be taken and the time or times of day when instruments will be read and possibly reset.

Time of Recording

For the observer starting a station with manually read instruments, the data is usually taken at a time in the morning, often 0900, for the following twenty-four hours and called the ‘terminal hour’. This time has to be convenient to the reader, must be the same for each day and each month, which also includes resetting any manually read instruments. In this group are the maximum and minimum temperature readings. The maximum reading is recorded for the previous day, which is referred to as ‘thrown back’. Conversely, the minimum is recorded on the day the thermometer is read, as the lowest temperature usually occurs, but not always, at dawn. For those who measure the rainfall manually, total precipitation for the previous twenty-four hour period will come into this group, which is ‘thrown back’ to be noted under the previous day. A reading for the barometric pressure will need to be taken at this time. Lastly, a reading for the current wind speed and direction could be noted if this equipment is installed.

If finance allows the purchase of a more advanced automatic weather station, much more information is available that can be read from the monitor. This system often has a facility for looking back at recorded data that can be stored for a limited time period. Often there is the possibility of purchasing a data logger for these advanced stations with related computer software. This facility enables the observer to download the data to a computer, at a time convenient for the observer, from which the information can be interrogated for specific twenty-four hour periods also being able to look back over data since the equipment was installed. This equipment enables the observer to have a continuous stream of daily statistics that are unbroken when the routine daily observations cannot be taken due to absences that are inevitable, such as for holidays and work commitments. Ultimately, data can be graphed, but more details of this in the following chapter.

From such advanced stations sunshine and solar radiation totals are recorded, if the relative sensors have been installed, for the period starting at midnight. This time for recording is called the ‘civil day’. Additional data under this category includes sunshine, solar radiation, solar energy, evaporation, ultra violet radiation and humidity.

Suggested Methods of Recording

A decision will need to be taken on the method of recording. It is important that this is convenient to the observer, as it will become a daily routine. Consideration must also be taken into the amount of data noted on a daily basis.

Initially, if just maximum and minimum temperatures along with rainfall are being recorded, a notebook with lined pages, that have vertical columns added manually, might suffice. Four vertical columns that allow for the date of reading would be quick and easy to produce for a start up station.

August – 2014

Maximum (C.)

Minimum (C.)

Rainfall (mm)

Notes

1

2

3

At a later point in time, as additional equipment is obtained, adding further columns for the recording of wind speed and direction at the time of reading might be enhance the database. Lastly, descriptions of the weather at the time of reading, or a synopsis at the end of the day might be included to give a fuller picture of the weather on each day.

If the likelihood is that the station will be operational for several years, consideration should be given to a more standardized recording sheet. Using a computer and a programme such as Excel in the Office Suite of software, the most appropriate grid can be designed for your individual needs and printed off for the manual, daily recording. At an appropriate time the data can be uploaded to a computer for a more permanent record that will allow further analysis if required. More details are included in chapter 12.

The observer might then wish to adapt the Excel sheet to highlight specific aspects of the data, such as temperatures below freezing. Additionally, the font colour might changed from black to red or blue, or whatever colour is most appropriate, in order for it to be more readily identified. This method will allow the observer to make a more useable and permanent sheet for each month, permit quick reference and facilitate further analysis.